The ozone hole over the Antarctic is likely to begin contracting in the future and may disappear by 2050 because of a reduction in the release of chlorofluorocarbons and other ozonedepleting gases, according to a team of Japanese scientists. The findings are based on a series of numerical simulations carried out by Eiji Akiyoshi of the National Institute for Environmental Studies, near Tokyo, using projected emissions of chlorofluorocarbons and other gases blamed for the ozone hole. According to a report posted Friday on the institute's website, the hole is at its largest now but is likely to gradually start contracting around 2020 and disappear by around 2050.